Design and evaluation of high power density brushless DC permanent magnet machines

Permanent Magnet brushless DC motors are now competing with many other types of motors in the world industries application. However, for low and medium power applications, brushless DC motors are often the main option due to its recognized advantage such as having no commutator, more efficient, need less maintenance, smaller in size and can operate at higher speeds than conventional motors. The overall objective of this project is to produce an improved prototype BLDC motor with concentrated winding concept for an aircraft actuator application. Specifically, the aim is to extract the maximum power density and torque per kilograms by utilizing high switching frequencies, high pole numbers and minimizing magnetic material content. In this work, the research has focused on developing a procedure to design the BLDC motor by selecting several parameters and analysing their effects on the overall performance. Therefore, this research involved software and hardware methods which are broken down into field and circuit modeling, calculation of basic dimensions, magnetic circuit calculations, stator slot design, winding design, performance and loss calculation and lastly prototyping. Magnet software for finite- element method (FEM) analysis and analysis programs based on standard software are used to optimize the overall performances. The proposed methods are verified by actual experimental result on the developed prototype. The performance of the prototyped machine is evaluated by using a high speed 150kw, 20,000 rpm test rig and data capturing equipment.EThOS - Electronic Theses Online ServiceGBUnited Kingdo